Your Mac is not compatible.
The Mac Pro 1,1 was released in 2006. Yosemite requires the Mac Pro 3,1 (2008) or later. Unfortunately, you are at the latest version of OS X that your Mac will support. See EveryMac.com for full details:
This system can run the last version of OS X 10.7 "Lion" if upgraded to at least 2 GB of RAM. However, although it has a ...
Direct link: https://updates.cdn-apple.com/2020/macos/061-90747-20200319-5ded2636-188e-428b-90e6-2ed1507f6f46/SecUpd2020-002HighSierra.dmg
in case it doesn't work, it's due to the key in between. Try the next link.
Download page: https://support.apple.com/downloads/macos
Generally speaking, a MacBook Air is not the best system for heavy users of CPU-bound applications like Final Cut Pro X and Logic Pro X. The primary reason for this is that the thinner chassis has less efficient cooling than a larger machine like a MacBook Pro, resulting in the CPU being more likely to throttle down to lower speeds more quickly when it gets ...
In your Container disk3 you have two volumes Macintosh SSD which is a read only volume of about 10GB and Macintosh SSD - Data containing your user files and other writable parts of the filesystem (logs, your installed applications etc). There are also some other small volumes not shown for recovery, booting etc that you can see with diskutil list
No way the new Air won’t run literal circles around anything from 2013.
ridiculously faster NVMe storage
Many generations better CPU never mind the I or GHz
Maybe spend up from the $999 model if you want a CPU for 3 years, but the entry Air is a powerhouse compared to most 2015 Macs.
Your MacBook Pro has a dual core i5-4258U CPU, which currently has average scores of 645/1,401 (single-core/multi-core) in Geekbench 5. There aren't yet enough scores of the latest (early 2020) MacBook Air but one early benchmark returned scores of 1,047/2,658.
This suggests that the MacBook Air should be almost twice as fast as your current MacBook Pro, ...